Self-Healing Gel Electrolytes for Flexible Supercapacitors

Abstract

Self-healing smart gels which can autonomously repair and restore damage have attracted tremendous interest for energy storage applications. The advent of the internet of things and the recent advances in wearable electronics mandate flexible energy storage devices like supercapacitors as an energy source. The solid-state polymer gels with appreciable ionic conductivities and tunable mechanical properties are inevitable for the facile fabrication of flexible and stretchable supercapacitors. Introducing the self-healing ability to the polyelectrolyte enables the independent restoration of device performance, while subjected to repeated mechanical damage. The self-healing gels repair the damages or cracks instantaneously by dynamic molecular interactions and maintain the ionic conductivities and conformal adhesion with the electrode surface. Following a concise introduction and an overview of self-healable gels, the chapter summarizes various strategies adopted for synthesizing smart gel electrolytes. The performances of various self-healing gels, assembled in flexible supercapacitors, and their energy storage efficiencies are discussed. In addition, the effect of redox mediators in the gel electrolytes and their synthesis protocols and application in stretchable supercapacitors are highlighted.